MACROMOLECULAR RESEARCH
·
2012
·Vol. 21
·期 6
·681-686
·
IF 1.153
Xu Yewei,Tang Jie,Chang Guanjun,Zhu Fanghua,Luo Xuan,Zhang Lin
Poly( N -arylenebenzimidazole ketone ketone)s (PNABIKKs) consisting of m - and p -phenylene linkages have been synthesized by nucleophilic aromatic substitution from bis(benzimidazolyl) derivatives containing sulfonyl, carbonyl, and ether groups with activated aromatic difluorides in sulfolane at 210 °C in the presence of anhydrous potassium carbonate. The structures of the polymers were characterized by means of Fourier tramsfom infrared (FTIR), proton nuclear magnetic resonance ( 1 H NMR) spectroscopy, and elemental analysis, and the results were largely consistent with the proposed structure. Differential scanning calorimetry (DSC) and thermogravimetric analysis (TG) measurements demonstrated that polymers had high glass transition temperatures ( T
g
>220 °C) and good thermal stability with high decomposition temperatures ( T
D
>480 °C). These novel polymers also showed good solubility.
✓ 已验证
产品关联
DOI
高影响因子
CATALYSIS LETTERS
·
2012
·Vol. 143
·期 2
·200-205
·
IF 2.242
Zeng Yan,Wang Yanhua,Xu Yicheng,Song Ying,Jiang Jingyang,Jin Zilin
Abstract A thermoregulated ionic liquid and organic biphasic system composed of ionic liquid [CH 3 (OCH 2 CH 2 ) 16 N + Et 3 ][CH 3 SO 3
− ] (IL PEG750 ) with IL PEG750 -stabilized Pd nanoparticles and organic solvents, which allows for not only a highly efficient homogeneous catalytic reaction, but also an easy biphasic separation and reuse of catalyst attributed to the thermoregulated phase-transition property of the system, was employed for Heck reaction. The IL PEG750 -stabilized Pd nanoparticle catalyst exhibited high efficiency, more importantly, after reaction the Pd nanoparticle catalyst could be separated from products by simple phase separation and recycled for six times without evident loss of activity. Graphical Abstract A thermoregulated ionic liquid and organic biphasic system containing [CH 3 (OCH 2 CH 2 ) 16 N + Et 3 ][CH 3 SO
- 3
] (IL PEG750 )-stabilized Pd nanoparticles was applied to Heck reaction for the first time. The Pd nanoparticle catalyst exhibited high efficiency and good recyclability.
✓ 已验证
产品关联
DOI
高影响因子
FLUID PHASE EQUILIBRIA
·
2015
·
IF 2.2
Yinchuan Pei,Qinbo Wang,Xing Gong,Fuqiong Lei,Binwei Shen
Liquid–liquid equilibrium (LLE) data for ternary systems water + cyclohexane + cyclohexanol and water + cyclohexane + cyclohexanone were measured at (303.2–333.2) K and under atmospheric pressure. The reliability of the experimental tie-line data was checked by the empirical Othmer–Tobias correlation. The distribution coefficient and separation factor were used to investigate the distribution of cyclohexanol and cyclohexanone between water and cyclohexane. The results show that the distribution coefficient of cyclohexanol or cyclohexanone between organic and aqueous phases increases with the increasing content of cyclohexanol or cyclohexanone in water, and so does it with the increasing of temperature. By using the NRTL and UNIQUAC activity coefficient models, the experimentally determined LLE data, along with the LLE data for another ternary system water + cyclohexanol + cyclohexanone [G. Xing, W. Qinbo, L. Fuqiong, S. Binwei, J. Chem. Eng. Data 59 (2013) 1651–1655], were correlated simultaneously. Good agreements were obtained between the correlated and experimentally determined tie-line data. The binary NRTL and UNIQUAC interaction parameters were obtained. Furthermore, four sets of quaternary LLE data for water + cyclohexane + cyclohexanol + cyclohexanone were experimentally determined at 318.2 K. The experimentally determined quaternary LLE data were compared with the NRTL model predicted LLE data, and generally agreements were obtained. It further verifies the reliability of the obtained binary model parameters, and indicates the obtained parameters could be used for prediction, as well as design and optimization of the related separation process.
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2014
·Vol. 4
·期 87
·46689-46696
·
IF 3.708
Wei-fang Chen,Ling Pan,Li-fang Chen,Qiong Wang,Chang-cheng Yan
Nano zero-valent iron (nZVI) and activated carbon composites were synthesized and employed to remove hexachlorobenzene (HCB). Methods of impregnation and adsorption were employed to firstly load iron salt onto activated carbon, and thus loaded iron was then reduced to form zero valent iron. Results indicate that the method of iron loading significantly impacted the amount of iron and HCB dechlorination. In general, nZVI/activated carbon composite synthesized using an adsorption method showed considerably higher removal efficiency and dechlorination capability. More than 80% of the HCB was dechlorinated after 48 h. The dechlorination of HCB followed a stepwise pathway: HCB (hexachlorobenzene) → PCB (pentachlorobenzene) → 1,2,4,5 TeCB (tetrachlorobenzene) → TriCB (trichlorobenzene) → 1,4 DCB (dichlorobenzene) → MCB (monochlorobenzene). Compared with activated carbon or nZVI, nZVI/activated carbon composite showed much higher HCB removal. Analysis of mass partition on solid and aqueous phases indicates that most of the HCB and its dechlorination intermediates were retained on solids probably due to the strong adsorption on activated carbon. In summary, activated carbon performs three important functions: it alleviated the limitation of nZVI agglomeration, contributed to HCB removal due to its own adsorption capability and increased the resistance of nZVI against pH change.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CHEMICAL AND ENGINEERING DATA
·
2013
·
IF 2.004
Fuqiong Lei,Qinbo Wang,Xing Gong,Binwei Shen,Bingyan Mao,Xiang Ye
Liquid–liquid equilibrium (LLE) data for the ternary system water + cyclohexane + acetic acid have been measured at (303.2 to 333.2) K under atmospheric pressure. The Othmer–Tobias and Bachman equations were used to check the reliability of the obtained tie-line data. The experimental data were correlated by NRTL (nonrandom two-liquid) activity coefficient model, and the relevant interaction parameters were regressed with the experimental data. The predicted values by NRTL method show good consistency with the measured data. The obtained interaction parameters can be used in the calculation of LLE for the ternary system water + cyclohexane + acetic acid as well as for the design and optimization of the related separation process.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF SEPARATION SCIENCE
·
2015
·Vol. 38
·期 16
·2880-2886
·
IF 2.737
Xi Zhang,Xiaohuan Zang,Guijiang Zhang,Chun Wang,Zhi Wang
A mesoporous carbon was fabricated using MCM-41 as a template and sucrose as a carbon source. The carbon material was coated on stainless-steel wires by using the sol–gel technique. The prepared solid-phase microextraction fiber was used for the extraction of five volatile aromatic compounds (chlorobenzene, ethylbenzene, o -xylene, bromobenzene, and 4-chlorotoluene) from tea beverage samples (red tea and green tea) prior to gas chromatography with mass spectrometric detection. The main experimental parameters affecting the extraction of the volatile aromatic compounds by the fiber, including the extraction time, sample volume, extraction temperature, salt addition, and desorption conditions, were investigated. The linearity was observed in the range from 0.1 to 10.0 μg/L with the correlation coefficients ( r ) ranging from 0.9923 to 0.9982 and the limits of detection were less than 10.0 ng/L. The recoveries of the volatile aromatic compounds by the method from tea beverage samples at spiking levels of 1.0 and 10.0 μg/L ranged from 73.1 to 99.1%.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
HIGH PERFORMANCE POLYMERS
·
2015
·
IF 1.286
Yewei Xu,Yi Sun,Yonglin Lei,Jichuan Huo,Lin Zhang
This article presents a convenient polymerization route to synthesize poly(arylene ether)s containing N-arylenebenzimidazolyl groups. The novel polymers were prepared by a catalyst-free nucleophilic substitution reaction, in which the N–H and O–H sites were removed from 2-(2-hydroxyphenyl)-1H-benzimidazole with different activated difluorides containing carbonyl groups in sulfolane. The reaction was carried out in the presence of anhydrous potassium carbonate at 210°C. The structures of the polymers were characterized using Fourier transform infrared spectroscopy, proton nuclear magnetic resonance spectroscopy, and elemental analysis. The results show good agreement with the proposed structure. All resulting polymers show essentially amorphous patterns. Moreover, differential scanning calorimetry and thermogravimetric measurements show that the polymers have high glass transition temperatures (>209°C), good thermostability, and high decomposition temperatures (>425°C). Furthermore, the polymers also exhibit excellent solubility in common organic solvents.
✓ 已验证
产品关联
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2017
·
IF 4.798
Xiaoli Wang,Zhenlong Zhang,Jianqiang Qin,Wenjia Shi,Yuefeng Liu,Huiping Gao,Yanli Mao
In the present study, Er and Yb co-doped TiO 2 (Er-Yb:TiO 2 ) nanorod arrays were grown with a hydrothermal method , and perovskite solar cells were fabricated using them as an electron transfer material. The photovoltaic performance of the solar cells based on Er-Yb:TiO 2 was enhanced compared with that of solar cells based on un-doped TiO 2 . The power conversion efficiency of the solar cells on Er-Yb:TiO 2 increased to 13.4%, which is 20.8% higher than that of the solar cells based on un-doped TiO 2 . The experimental results indicate that the larger open circuit voltage could be due to the larger conduction band difference between Er-Yb:TiO 2 and perovskite material. The enlarged short circuit current could be attributed to the faster electron transfer, reduced recombination, and the upconversion of Er-Yb:TiO 2 NRs.
✓ 已验证
产品关联
DOI
高影响因子
Advanced Science
·
2017
·Vol. 4
·期 10
·1700008
·
IF 9.034
Xin Yao,Junhui Liang,Yuelong Li,Jingshan Luo,Biao Shi,Changchun Wei,Dekun Zhang,Baozhang Li,Yi Ding,Ying Zhao,Xiaodan Zhang
Intensive studies on low-temperature deposited electron transport materials have been performed to improve the efficiency of n-i-p type planar perovskite solar cells to extend their application on plastic and multijunction device architectures. Here, a TiO 2 film with enhanced conductivity and tailored band edge is prepared by magnetron sputtering at room temperature by hydrogen doping (HTO), which accelerates the electron extraction from perovskite photoabsorber and reduces charge transfer resistance, resulting in an improved short circuit current density and fill factor. The HTO film with upward shifted Fermi level guarantees a smaller loss on V OC and facilitates the growth of high-quality absorber with much larger grains and more uniform size, leading to devices with negligible hysteresis. In comparison with the pristine TiO 2 prepared without hydrogen doping, the HTO-based device exhibits a substantial performance enhancement leading to an efficiency of 19.30% and more stabilized photovoltaic performance maintaining 93% of its initial value after 300 min continuous illumination in the glove box. These properties permit the room-temperature magnetron sputtered HTO film as a promising electron transport material for flexible and tandem perovskite solar cell in the future.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
·
2017
·Vol. 19
·期 20
·13147-13152
·
IF 4.123
Tongyu Su,Xinhang Li,Yongzhuan Zhang,Fapei Zhang,Zhigao Sheng
The annealing temperature (Ta) effect on CH3NH3PbI3 perovskite solar cells (PSCs) was studied. By utilizing a two-step technique, the Ta dependences of the optical absorption, grain size, and crystallinity of a CH3NH3PbI3 thin film have been revealed. It is found that the grain size of the CH3NH3PbI3 film increases monotonically with Ta. Meanwhile, the decomposed PbI2 emerges when Ta exceeds 120 °C and its content increases rapidly as Ta increases further. Consequently, the optical absorption of the CH3NH3PbI3 film and the efficiency of PSCs reach their maximum at Ta = 120 °C simultaneously. The highest and average device performances of PSCs achieved via this method are 17.61% and 16.40%, respectively. These results confirm the key role played by temperature and provide a route to the performance-optimization of PSCs.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Light-Science & Applications
·
2024
·Vol. 13
·期 1
·1-11
·
IF 20.6
Zhang Dingshuo,Zhu Meiyi,He Yifan,Cao Qingli,Gao Yun,Li Hongjin,Lu Guochao,Cui Qiaopeng,Shen Yongmiao,He Haiping,Dai Xingliang,Ye Zhizhen
Broadband electroluminescence based on environment-friendly emitters is promising for healthy lighting yet remains an unprecedented challenge to progress. The copper halide-based emitters are competitive candidates for broadband emission, but their high-performance electroluminescence shows inadequate broad emission bandwidth of less than 90 nm. Here, we demonstrate efficient ultra-broadband electroluminescence from a copper halide (CuI) nanocluster single emitter prepared by a one-step solution synthesis-deposition process, through dedicated design of ligands and subtle selection of solvents. The CuI nanocluster exhibits high rigidity in the excitation state as well as dual-emissive modes of phosphorescence and temperature-activated delayed fluorescence, enabling the uniform cluster-composed film to show excellent stability and high photoluminescent efficiency. In consequence, ultra-broadband light-emitting diodes (LEDs) present nearly identical performance in an inert or air atmosphere without encapsulation and outstanding high-temperature operation performance, reaching an emission full width at half maximum (FWHM) of ~120 nm, a peak external quantum efficiency of 13%, a record maximum luminance of ~50,000 cd m −2 , and an operating half-lifetime of 137 h at 100 cd m −2 . The results highlight the potential of copper halide nanoclusters for next-generation healthy lighting.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ADVANCED MATERIALS
·
2024
·
IF 27.4
Wenshu Yang,Kai Zhang,Wei Yuan,Lijun Zhang,Chuanjiang Qin,Haibo Wang
Ion migration poses a substantial challenge in perovskite transistors, exerting detrimental effects on hysteresis and operational stability. This study focuses on elucidating the influence of ion migration on the performance of tin-based perovskite field-effect transistors (FETs). It is revealed that the high background carrier density in FASnI 3 FETs arises not only from the oxidation of Sn 2+ but also from the migration of FA + ions. The formation of hydrogen bonding between FA + and F − ions efficiently inhibits ion migration, leading to a reduction in background carrier density and an improvement in the operational stability of the transistors. The strategy of hydrogen bond is extended to fluorine-substituted additives to improve device performance. The incorporation of 4-fluorophenethylammonium iodide additives into FETs significantly minimizes the shift of turn-on voltage during cyclic measurements. Notably, an effective mobility of up to 30 cm 2 V −1 s −1 with an I on/off ratio of 10 7 is achieved. These findings hold promising potential for advancing tin-based perovskite technology in the field of electronics.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）